That's a great feature, really helpful when migrating JSF applications from an older AS. It's fully working with JBoss AS 7.2 (jboss-as-7.2.0.Alpha1-SNAPSHOT). On JBoss AS 7.1.3 (or EAP 6.0.1), the feature is only partial.
For example, @EJB injection doesn't work with my JSF 1.2 managed beans :( . And the jsf subsystem doesn't exist yet. On my application, I had to make a custom InjectionProvider to have my EJBs injected.
I'm really looking forward to have that new release.